EMAX Lawnmower Improvements for 2013 Sales Season Paul

EMAX Lawnmower Improvements for 2013 Sales Season Paul Hodgson Design Engineer

Project Objectives • This project was initiated to address the various quality and performance concerns related to the EMAX lawnmowers that have arisen during their first season in the marketplace • From the analysis of these concerns it has been possible to identify the contributory faults and devise solutions. These solutions and implementation details are illustrated in the following slides 2

EMAX 32 1. Switchbox / Handle Improvements 2. Transmission Improvements (motor, belt, housings) 3

1. EMAX 32 Switchbox / Handle Improvements 1 a. Additional screw bosses to improve switch location 1 d. Additional ribs added in housing to retain lock button when actuated 1 b. Lever actuator thickened to increase rigidity 1 e. Uprated lever sping to ensure lever fully retreats upon release 1 c. Lock button / lever interface redesigned to ensure positive engagement and correct actuation of switch Issue: Intermittent switching or no power. Lock button releases whilst in use Status: Implemented as Type 2 on all SKUs, week 34 4

1. EMAX 32 Switchbox / Handle Improvements 1 f. In redesigning lock button / actuator interface, switching postion has been moved earlier in stroke. More over travel Issue: Switching point to close to handle, user needs to grip lever tightly and constantly to avoid interuptions in power supply Status: Implemented as Type 2 on all SKUs, week 34 5

1. EMAX 32 Switchbox / Handle Improvements 1 g. Dimensional changes to screw bosses and supporting ribs to secure switchboxes to handle and limit rotational movement Issue: Switchbox not secured to handle, even though screws are fully engaged. Can cause switching problems and suggests low quality Status: Implemented as Type 2 on all SKUs, week 34 6

2. EMAX 32 Transmission Improvements 2 a. Material change on main structural components to BMC. This gives improvements in terms of dimensional and temperature stability. Fundamentally, it is a more rigid material which will allow a lower belt tension, thus reducing stress on all connected components within the transmission Issue: Early transmission failures, snapped armature shafts, melting of bearing housings & belts cutting through deck Status: Target implemetation week 44 7

2. EMAX 32 Transmission Improvements 2 b. Extra grinding operation added to manaufacture of armature shaft to ensure that assembled pinion meets runout specification 2 c. Belt retenion lip increased on gear wheel Issue: Early transmission failures, snapped armature shafts, melting of bearing housings & belts cutting through deck Status: Program of testing underway, target implementation week 40 8

EMAX 34 / 38 3. Switchbox / Handle Improvements 4. Transmission Improvements (motor, belt, housings) 9

3. EMAX 34 / 38 Switchbox / Handle Improvements 3. All switchbox changes are the same as described on EMAX 32 Issue: Intermittent switching or no power. Lock button releases whilst in use Status: Implemented as Type 2 on all SKUs, week 34 10

4. EMAX 34 / 38 Transmission Improvements 4 a. Belt retenion lip increased on gear wheel 4 b. Extra grinding operation added to manaufacture of armature shaft to ensure that assembled pinion meets runout specification Issue: Early transmission failures, snapped armature shafts & belts cutting through deck Status: Program of testing underway, target implementation week 40 11

EMAX 42 5. Switchbox / Handle Improvements 6. Transmission Improvements (motor, belt, housings) 12

5. EMAX 42 Switchbox / Handle Improvements 5 a. Internal modifications as described on EMAX 32/34/38 Issue: Status: 5 b. Pivot support location improved to ensure positive switching over complete length of bale bar Intermittent switching or no power. Lock button releases whilst in use Implemented as Type 2 on all SKUs, week 34. Pivot location improvements week 40 13

6. EMAX 42 Transmission Improvements 6 a. Belt retenion lip increased on gear wheel 6 b. Extra grinding operation added to manaufacture of armature shaft to ensure that assembled pinion meets runout specification Issue: Early transmission failures, snapped armature shafts & belts cutting through deck Status: Program of testing underway, target implementation week 40 14

EMAX 34 / 38 / 42 Grassboxes Standardise clip dimensions on EMAX 34 & 38 grassboxes to match those on EMAX 42 EMAX 34 & 38 grassbox clips will be modified when production schedule allows access to mould tools. There is no functional problem with EMAX 34 & 38 grassboxes as they are currently being produced, the modification is to standardise dimensions across all SKUs 15

Implementation Summary Issue Affected Models Solution Intermittent switching or no power. Lock button releases whilst in use EMAX 32/34/38/42 Redesign of internal mechanism Week 34 Switching point too close to handle EMAX 32/34/38/42 Redesign of internal mechanism Week 34 EMAX 32/34/38/42 Modifications to screw bosses and supporting ribs Week 34 EMAX 32 Change material of transmission bracket and bearing housings to BMC type material Week 44 Snapped armatures & belts cutting decks EMAX 32/34/38/42 Extended belt retaining lip & armature shafts to have ground pinion mounting surface. Week 40 Bale arm pivot can become dislocated in housing EMAX 42 Increase are of location in pivot housing Week 40 Switchbox loose on handle Snapped armatures, melted bearing housings & belts cutting decks Proposed Implementation 16